as Intelligence Officer with the Black Watch. He was promoted to Brevet-Major and three times mentioned in dispatches. Explorer Following the Armistice, Mason was the first to take motor cars across the Syrian Desert. He then returned to India and, in 1926, began preparing for his most important scientific project, the exploration of the Shaksgam Valley in Xinjiang, China. The valley lies to the north of Baltoro Muztagh, a subrange of the Karakoram mountain range that includes K2, the second highest mountain in the world. In the context of long-running political rivalry between world powers that became known as the Great Game, over several decades interest of the British Imperial authorities in this unmapped and uninhabited territory had been growing, because it provided access to the Aghil Pass linking China to Ladakh, India. However, the only westerner to see the valley had been Francis Younghusband, whose book The heart of a continent : a narrative of travels in Manchuria, across the Gobi Desert, through the Himalayas, the Pamirs, and Chitral, 1884-1894 had first inspired Mason as a schoolboy to pursue a career in geography. Now, Younghusband encouraged Mason to follow in his footsteps. With support from the Royal Geographical Society (RGS), Mason set out from the south, surveying using a photo-theodolite and aiming to reach the Shaksgam Valley from the Karakorum Pass. He explored the Aghil range in the Karakoram fault system and confirmed the source of the Shaksgam river, then planned to follow the valley downstream. However, when several glaciers blocked the valley and had to be bypassed, Mason's expedition ended up in a similar looking valley, parallel and northeast of the true Shaksgam valley. By the time Mason realized the mistake, supplies were running low, and the only option was to retreat so he named the previously unknown valley Zug Shaksgam (“false Shaksgam”). Mason returned to Europe with great quantities of data representing the first attempt to apply stereographic techniques to both small scales and great distances. His results, plotted in Switzerland using what, at the time, was the world's most advanced Stereoplotter were acclaimed as brilliantly successful, winning him the 1927 RGS Founder's Medal. In 1928, Mason and Geoffrey Corbett convened a group to co-found The Himalayan Club, "To encourage and assist Himalayan travel and exploration, and to extend knowledge of the Himalaya and adjoining mountain ranges through science, art, literature and sport." Mason edited the club's